There Are Some Seriously Pyschedelic Bacteria Living on Your Teeth

Like every other surface of your body, your mouth is teeming with a panoply of bacteria. It’s a thought most of us try to keep buried in the backs of our minds, but a new study shows that the tiny communities flourishing between your molars can be quite pretty. In a kaleidoscopic nightmare-fuel sort of way.

From spherical Streptococcus to oxygen-fearing Fusobacterium, the human mouth is a spawning ground for tiny, unseen organisms. But until very recently, it was difficult to say which of these critters lived where. The gold standard for studying microbial communities is DNA sequencing—but extracting DNA from a spec of plaque is like sticking a forest in a blender. Your analysis might tell you a lot about who you just juiced, but you sure as hell won’t be able to figure out what that ecosystem looked like.

A kaleidoscopic view of the plaque microbiome.

To study the architecture of the communities our gum-loving compatriots build, Jessica Mark Welch of the Woods Hole Marine Biological Laboratory and Gary Boris of the Forsyth Institute took a different approach. They collected scrapings of dental plaque from 22 brave humans, and smeared each onto a microscope slide. The slides were then washed with several biological markers; molecules that light up different colours when they lock onto specific bacteria.

It took a while to refine the process, but eventually, the researchers had markers covering over 96 per cent of the microbes in human plaque. And once everything was working properly, the psychedelic beauty of our poor dental hygiene was revealed. Have a gander, and tell me science isn’t the greatest of all human endeavours.

Another plaque microbial community, bursting with color like a starburst galaxy

But apart from horrifying the hypochondriacs in the room, is there any point to visualising our microbial consorts like this? Of course there is! By understanding the spatial structure of microbial communities, we can start to learn what their ecological roles are—including which ones are benign and which ones our arsenal of anti-tooth decay products should be targeting. As with any other ecosystem, there’s a certain balance we’d like to to maintain in the mouth, and the first step toward doing so is understanding what we’re looking at.

Plus, I bet you’ve never thought to compare your teeth to a starburst galaxy before.